This is my first post on the forum, but I have been reading for some time.

I have a medium sized bitch on day 45 of her pregnancy and I am currently shopping for everything I'll need for whelping.

I have been steered towards using hot water bottles to keep the pups warm when they arrive - both in the hot box and the whelping box, but the hassle free nature of a heat pad also appeals.  I have a heat lamp from hatching chicks, but think I would rather not use that.

Is there a favoured heat pad?  I have found soft ones and metal ones, ones with armoured cable and ones without.  Which is best?  And I see some people put it underneath the vet bed and some on top - what's the consensus?

I got one off ebay with a fleece cover, really cheap, about £10 I think.  My puppies used it for couple of weeks and I used it over the Vetbed.

I am not planning any more litters for at least a few years, so I went for cheap and cheerful.

I used a crate to whelp, so was unable to rig up a heat lamp, but in some ways I think they are better.

Once mine were starting to move about they rarely used it - medium gundog breed - they used to go under it though rather than lie on top!

http://www.petnap.co.uk/acatalog/pet-heat-pads.html#a30

scroll down to flexiguard.

Best thing I've ever used.  And I've tried most.  I would never use a lamp again.  The flexiguard does fine for me.  I put it under the vetbed and the weight of pups on top is what seems to create the correct warmth.  Mum can move away if she's too hot, and when she does move it is amazing how the pups are drawn towards the pad.  I have a tiny breed, so if they are very tiny pups I will put a fleece cover on the pad, and put pups right on it. 

Having reared a Yorkie litter years ago and used a vinyl pad I soon found out that pups eat them!  The flexiguard is indestructible.  I don't like the idea of hot water bottles, they don't keep warm long enough, and I would worry about scalding if one sprang a leak.

Things do move on but when we were doing our litters, we used a Brood Lamp.   I had to drape a sheet across the back of the box so mum could get away from immediately under the lamp, but this gave a good overall warmth for my litters.

I always worried about electric leads anywhere near the puppies.   I'd not use a hot bottle, for the same reasons as have been given here.

>I always worried about electric leads anywhere near the puppies.

Which is why I use flexiguard.  It is indestructible.

I have a heat pad at hand but I keep my whelping room really warm so I haven't needed to used it. I have a large metal one with a metal covered flex - wouldn't feel safe with anything else.
When I first read the Book of the Bitch many, many years ago, it recommended keeping the whelping room warm and humid and this is just what I do. I would worry that a heat lamp might be a bit drying ...
I would never use a crate to whelp in or keep new puppies in. My personal preference of course, but I want easy access to any area of the whelping box instantly, in case a pup is in difficulties for whatever reason. Many bitches are not very careful about squashing their puppies.
I have just had my first litter in nearly 12 years, and after seeing pics of puppies from the Scandinavian countries in the big square "faux leather" dog beds, with raised sides of about 4 inches, I thought I'd give it a try as I already have one. What a good decision it was! Really easy to reach everywhere and lovely and easy on my knees as it's nice and squishy, and lovely and comfortable for my girl :) I've got a layer of newspaper and a thick bit of vet bed on top, both of which are changed at least a couple of times a day and I quickly disinfect the bed. They were born in the early hours of Friday morning. They are constantly accompanied so it's not a worry that they could climb out now, but I will probably put the whole thing inside my whelping box later today for added security.
We all do things in different ways, and this has worked well for me :)

Thank you for the advice - it looks as though a metal heat pad is the most popular thing, I can see why.  It looks to be pretty worry free which is just what I'm hoping for.

A vote here for the metal pet nap heat pad. For some reason you're not meant to put it under vet bed though :)
I also got a microwaveable snugglesafe one too, which quickly became an invaluable piece of whelping kit when my bitch needed an emergency Caesarian so the pups came back in the car snuggled up in a plastic box with this :)

What about one of those old-fashioned stone hot water bottles? Unbreakable, unchewable, won't leak if the rubber washer is in good condition, and wrapped up in some fleece or a towel, they can snuggle up to it as if it was their mum. They stay warm for a long time - up to 12 hours.

They are also lovely in your own bed to put your feet on in the winter!

I would worry that a heat lamp might be a bit drying ...

Just to add that rather than being too drying, actually the brood lamp was useful to dry out the 'moisture' LOL.